Google has taken a sanguine attitude towards the issue, perhaps because as Adblock Plus creator Wladimir Palant notes, "Ad blockers are still used by a tiny proportion of the Internet population, and these aren't the kind of people susceptible to ads anyway." (In other words, the users most likely to download an ad blocking extensions, are likely to be more "ad-blind" and less likely to click on ads anyway.) Google's director of engineering has noted how cautiously Google weighed its decision to allow ad-blocking programs "because Google makes all of its money from advertising." But in the end, as the Times notes:

[H]e explained that the prevailing thinking was that "it's unlikely ad blockers are going to get to the level where they imperil the advertising market, because if advertising is so annoying that a large segment of the population wants to block it, then advertising should get less annoying."

"So I think the market will sort this out," he said. "At least that is the bet we made when we opened the extension gallery and didn't have any policy against ad-blockers."

Michael Gundlach, creator of the AdBlock extension for Chrome (no direct connection to Palant's AdBlock plus for Firefox, despite the similar names),

who once worked for Google in Ireland helping to ensure that ads kept appearing on Web sites, says he does not fear for media companies that increasingly rely on online ad revenue. Sounding like a firm believer of Mr. Rosenberg's embrace-the-chaos manifesto, Mr. Gundlach said a brighter day would emerge from the challenge of ad blockers.

Extensions like his, he said, will make "every one else change their ways, to make ads more useful. Everyone wins, that's competition. The ideal result would be to retire this extension because the entire Web was covered with ads that people loved and no one wanted to block them."

Absent any rules, every individual [television] advertiser has an incentive to jack up the volume in order to attract attention, and doing so will probably work up to a certain point of increased annoyance by the user. But collectively, such ads hurt all advertisers because they increase ad blindness, ad deafness, and/or outright commercial skipping. The same dynamic plays out on the Internet, where flashing, blinking, bouncing, strobing dancing ads really drive users nuts and make them turn to tools like AdBlock Plus and Flashblock--which is why ad networks like Google have policies that implement their own "time, place and manner" rules out of pure self-interest. Such rules are useful and valuable. They benefit advertisers, consumers and the ad network alike, because there exists a basic harmony of interests between them: annoying ads don't really benefit anyone in the long-term.

There is, however, one important difference between these Chrome extensions and AdBlock Plus: ABP will block the download of content from any domain specified on a black list, including cookies, which makes ABP a powerful privacy management tool as well as a tool for controlling annoying ads, as Adam Thierer and I noted in our "Privacy Solutions" entry on AdBlock Plus. By contrast, the Chrome API doesn't allow extensions to block the downloading of content, but does allow these extensions to block the display of certain elements.

While someone is sure to suggest that this represents an unacceptable deviation from Orthodox Openness, there doesn't seem to be any reason to think that this technical decision was motivated by a desire to prevent the blocking of tracking cookies. After all, Chrome already includes cookie management tools in its privacy settings panel, including the ability to block third party ad cookies. (Careful readers will notice that the third-party-cookie-blocking option will only allow "Third-party cookies [to] be sent if you've explicitly visited those third-party sites in the past." That seems like a particularly effective way to structure the system, since users are unlikely to ever visit the domain from which a third-party ad-tracking cookie is served. For example, Google's tracking cookies come not from www.google.com, which most users visit regularly, but from www.doubleclick.net and www.googleadservices.com, which no user will likely ever visit. So Google isn't trying to pull a fast one here.)

The difference between Chrome's built-in privacy management functionality and what AdBlock Plus in Firefox allows is simply a matter of granularity: ABP will let you subscribe to a cookie blacklist to engage in "targeted blocking of cookies from data-collectors to whose privacy practices you might object. As Adam and I have said repeatedly, such granularity of control is a good thing and would move us closer towards the "ideal world" in which:

adults would be fully empowered totailor speech and privacy decisions to their own values and preferences. Specifically, in an ideal world, adults (and parents) would have (1) the information necessary to make informed decisions and (2) the tools and methods necessary to act upon that information. Importantly, those tools and methods would give them the ability to not only block the things they don't like--objectionable content, annoying ads or the collection of data about them--while also finding the things they want.

I hope Google will eventually move in that direction, but I won't even begin to presume to know how thorny the technical implementation of a content-download-blocking functionality such as permitted by the Firefox API would be.